In rowing, proper assembly of the rowing equipment includes measurement of pitch. In other applications and contexts, pitch measurements also are needed.
The measurement of an angle relative to the local direction of gravity is commonly performed by electronic level and tilt meters available today. However, many applications require the measurement of the angle between two surfaces, neither of which is parallel or perpendicular to the direction of gravity (what construction trades call plumb or level, respectively). What is needed, and many applications require, is a reliable and accurate device which can measure the angle of one surface relative to another surface, even if those two surfaces are not physically attached or in close proximity to one another.
It is noted that patent literature includes the following:
U.S. Pat. No. 5,381,604 issued Jan. 17, 1995 to Heidel et al., titled “Angle measurement device employing angle sensor and electronics integrally formed on a printed circuit board.”
U.S. Pat. No. 5,488,777 issued Feb. 6, 1996 to Erdesky, titled “Utility line angle measurement device.”
U.S. Pat. No. 5,511,320 issued Apr. 30, 1996 to Heidel et al., titled “Angle measurement device employing angle sensor and electronics with lead circuitry integrally formed on a printed circuit board.”
U.S. Pat. No. 6,192,595 issued Feb. 27, 2001, to Stewart, titled “Gauge for use with an instrument for measuring the pitch of an oar blade.”
U.S. Pat. No. 6,715,213 issued Apr. 6, 2004, to Richter, titled “3D Angle measurement instrument.”
U.S. patent publication no. 20040186695 by Aoshima, et al., published Sep. 23, 2004, titled “Body motion detection device, pitch meter, wristwatch-type information processing device, method for controlling thereof, control program, and storage medium.”
U.S. Pat. No. 6,871,413 issued Mar. 29, 2005 to Arms et al., titled “Miniaturized inclinometer for angle measurement with accurate measurement indicator.”
U.S. patent publication no. 2006/0005408 dated Jan. 12, 2006 by Fernand, titled “Multipurpose angle measurement tool.”
It also is noted that sometimes “pitch” is used in certain literature with a different meaning than the term “pitch” herein.
However, conventional approaches for measuring pitch have been difficult to use, even for an experienced user. This ease-of-use problem is experienced, for example, by rowers (even experienced rowers) using conventional pitch meters. Several mechanical devices exist which can perform the angle measurement wanted, however, these mechanical devices generally rely on a spirit level to achieve their relative measurements, and are only accurate to how well the user can interpolate the scale on the device. These mechanical devices require great skill to obtain accurate and repeatable measurements.